Five senior Scottish judges have begun hearing an appeal by the man convicted of the 1988 Lockerbie bombing.

Abdelbaset ali Mohmed al-Megrahi was found guilty in January 2001 of bombing Pan Am 103 over Lockerbie and killing 270 people.

Lawyers for al-Megrahi told the appeal judges that fresh evidence has emerged which casts doubt on the guilt of the Libyan.

The Crown is contesting the appeal move claiming the new evidence is not materially important to the case.

In a Scottish legal first, the appeal, which is being heard at Camp Zeist in the Netherlands, is being broadcast live on television and on the internet.

Al Megrahi is appealing against his conviction

Al-Megrahi's co-accused, Al Amin Khalifa Fhimah, a former station manager for
Libyan Arab Airlines, was acquitted at the end of the original trial after the
judges ruled there was no evidence he had helped plant the bomb.

An appeal against conviction was lodged by al-Megrahi in June 2001.

He had been sentenced to a minimum of 20 years in jail after a nine-month trial in a specially convened Scottish court at Camp Zeist.

A panel of five judges, headed by Lord Cullen, the Lord Justice General, was
selected last week to hear the appeal.

New evidence

Lawyers for al-Megrahi told the judges they planned to produce fresh evidence
at the hearing.

William Taylor QC said one of al-Megrahi's grounds of appeal would be "an
application to the court to receive fresh evidence and then the hearing of that
evidence, if your lordships are of a mind to permit that evidence to be
heard".

Alan Turnbull QC, for the Crown, argued that the evidence was not sufficient to justify being heard in the appeal.

Mr Taylor said that with the exception of the new evidence, the grounds of
appeal constituted criticisms of the findings of the judges in their 82-page
opinion, which was issued at the end of the original trial.

He said he intended to show that the three judges had effectively misdirected themselves as jurors and led to a miscarriage of justice.

270 people were killed in the bombing

Mr Taylor said he would argue that the verdict reached by the original court
was not one that a reasonable jury in an ordinary trial could have reached if it
was given proper directions by the judge.

According to the prosecution's version of events, which was accepted by the
three judges in the trial, the suitcase carrying the bomb which blew up the
plane was loaded onto a plane in Malta.

From there it was transported via Frankfurt to Heathrow, where it was loaded
onto Pan Am flight 103.

Al Megrahi's defence team has always insisted the bomb suitcase was more
likely to have been placed on board the plane at Heathrow and wants to introduce
new evidence to support that claim.

It wants to hear fresh testimony from Heathrow security guard Ray Manly who has claimed there was a break-in at the baggage build up area at Heathrow airport on December 21 1988, the same day Pan Am flight 103 took off from there bound for
America.

Reliability of evidence

The defence will also launch a fresh attack on the evidence of Tony Gauci, a
Maltese shopkeeper who identified al-Megrahi as a man who had bought clothing at his store a few weeks before the bombing.

Shreds of the same clothing were found scattered around Lockerbie as the
debris of the plane was recovered and evidence was produced to indicate it had
been packed around the bomb.

Defence lawyers in the trial questioned the reliability of Mr Gauci's evidence
and the panel of judges admitted he had not made an "absolutely positive"
identification of al-Megrahi either in court or from photographs.

The defence team issued a nine-page submission at the start of the hearing
detailing their grounds for appeal.

The appeal hearing has made legal history as its opening scenes were shown
live on television and the internet.

TV footage will also be used in news bulletins, although broadcasters will be
subject to a number of restrictions, including a ban on televising evidence from
witnesses.